Nitrate – toxicity, side effects, diseases and environmental impacts

Nitrate and nitrite are naturally occurring chemical compounds found in soil, water, plants and even our own bodies. They typically exist in the environment in highly water-soluble forms, in association with other ions such as sodium and potassium.

Nitrate is generally stable in the environment, but it may be reduced to nitrite through biological processes involving plants, microbes, etc. In nature, plants utilize nitrate as an essential nutrient.

Majority of nitrate is used in inorganic fertilizers. Additional uses of commercial nitrate and nitrite include food preservation (added to processed meats like bacon) and the production of munitions and explosives.

List of known side effects

Inhalation or ingestion of nitrate vapors or fumes may cause the following side effects (based on animal tests):

Brown discoloration of visible mucous membranes

Colonic convulsions

Dullness

Dyspnea

Frequent muscle tremor

Incoordination

Mild depression

Partial anorexia

Recumbency

Salivation

Further studies on animal models showed reproductive toxicity associated with intake of high levels of nitrate and nitrite. In addition, no teratogenic effects were observed in rats, mice, rabbits or hamsters.

The studies further conclude that nitrate itself was not genotoxic (damaging to DNA). The results of carcinogenicity studies were negative except in extremely high doses, although it has been noted that nitrite may form molecules in the class called nitrosamines including one carcinogen known as dimethylnitrosamine. This class of N-nitroso compounds tends to have carcinogenic potential, but epidemiological studies consistently showed no increased risk for cancer with increasing consumption of nitrate.

Chemical compounds exposed to fire may produce irritating, corrosive and/or toxic gases. Some may decompose explosively when heated or involved in a fire. Runoff from fire control or dilution water may cause pollution.

Body systems affected by nitrate

High doses of nitrate also affect the kidneys, adrenal and thyroid glands, and gastrointestinal tract, based on animal studies.

Human saliva contains nine milligrams per liter (9 mg/L) of nitrite due to oral bacterial metabolism. Ingested nitrate can convert into nitrite in the mouth.

Items that can contain nitrate

Celery, leafy greens, beets, parsley, leeks, endive, cabbage, and fennel are the most potent sources of nitrate, but you’ll get some nitrates from almost any plant you eat. Around 80 percent of our nitrate consumption comes from vegetables, according to the Centers for Disease Control and Prevention (CDC), with about 21 percent being accounted for by drinking water.

Nitrates and nitrites are also used in food preservation in cured meats such as bacon, bologna, ham, hot dogs, salami, sausages and other cold cuts. These compounds can also be found in canned lunchmeat and other packaged foods.

How to avoid nitrate

Nitrates and nitrites can be found in many food items, especially processed meats. Take note of the following ways to keep these chemical compounds out of your body:

Minimize your consumption of processed meats.

Eat more organic food.

Eat a diet high in antioxidants and other vitamins.

Check labels on food items for sodium or potassium nitrates and nitrites.

Find out if your water is tainted with nitrates or nitrites. Have your drinking water tested in a laboratory or have your local health department check for these compounds and disclose the results publicly.

Summary

Nitrate and nitrite are naturally occurring chemical compounds found in soil, water and plants. These compounds are also present in the human body, particularly int the mouth, where saliva contains nine milligrams per liter of nitrite.

Nitrate is also used in inorganic fertilizers and as food preservatives in processed meats. Many vegetables also naturally contain nitrates and nitrites.